MANAGING YOUR SALINITY

Transcription

1 MANAGING YOUR SALINITY IRRIGATION WITH SALINE GROUNDWATER AND RO CONCENTRATE FOR FOOD SECURITY IN ARID/SEMIARID AREAS MANOJ K SHUKLA, Ph.D. NAKAYAMA PROFESSOR AND CHAIR DEPARTMENT OF PLANT AND ENVIRONMENTAL SCIENCES NEW MEXICO STATE UNIVERSITY, LAS CRUCES, USA March 11, 2017, Hernandez Hall

2 UN Projections in 2010 World Population Model Projections: 2 of 3 show growth Food Security? Water for Irrigation?

3 Water Scarcity Across the World IWMI International Water Management Institute Annual Report 2007

4 Elephant Butt Reservoir T OR C, New Mexico Aug 2016: ~2% capacity from 2.6 M acre-ft

5 Acre-inches per acre Water Allotment to NM Farms by EBID 36* Year * 36 acre-inches per acre is considered as full allotment. Less than adequate for most years

6 Surface Water Availability for Irrigation in NM is declining And will the situation improve???? How is our groundwater?

7 Depth to groundwater with total dissolved-solids concentration (TDS) greater than 1,000 milligrams per liter in the United States (modified from Feth and others, 1965)

8 Water Type TDS (mg/l) Fresh <500 Brackish ,000 Saline 10,000-35,000 Brine 35, ,000 Salt Saturated >250,000 Aquifer water salinity is variable Usually deeper aquifers are more saline

9 Total volume of water in aquifers in New Mexico = 20 billion acre-feet Not available everywhere 75% is too saline 25% < 2000 mg/l NMWRRI Trans-boundary Aquifer Assessment (Hawley and Kennedy, 2004)

10 Groundwater increasingly used for irrigation Groundwater aquifers not contiguous About 75% of the groundwater- brackish (>3 ds/m; > 2000 ppm) Can chile-pepper production be sustained in New Mexico?

11 Use of Brackish Groundwater: Treated and Untreated Using Untreated for Irrigation will Increase soil salinity Is there enough fresh water for leaching? Treating brackish water: GOOD for soil How to Treat brackish water?

12 BGNDRF, Alamogordo, NM KBHD facility, El Paso, TX New plant will have 1 MGD, expandable to 6 MGD 27.5 million gallons of fresh water daily (MGD) Is Desalination a viable option for cleaning saline water in NM? What to do with the Concentrate? And other constituents? Deep well injection Evaporation pond Agriculture?

13 Objectives How will irrigation with brackish groundwater and reverse osmosis (RO) concentrate change chile pepper: seed germination? height at different stages? yields? Chile pepper varieties selected were: AZ 1904, NuMex Joe E. Parker, NuMex Sandia Select, LB25, 3441

14 Brackish groundwater and Reverse Osmosis (RO) concentrate was provided by Brackish Groundwater National Desalination Facility, Alamogordo, NM Water EC SAR Mg Ca Na K Cl SO 4 mg/l mg/l mg/l mg/l mg/l mg/l mg/l Brackish GW Brackish GW RO Concentrate

15 4 Irrigation Salinity treatments: Tap water of EC 400 ppm(control), Brackish groundwater of EC 1300, 1700, 2000, 2600 ppm 4 seeds placed within 1-2 cm soil depth Irrigation treatments applied at 3-4 days interval Emergence recorded every 2 days Healthy plants transferred into bigger plots for survival, growth, and yield Brackish groundwater of EC 2000, 3300 ppm RO concentrate of EC 5300 ppm Baath et al Agricultural Water Management- Journal

16 NO. OF SEEDS EMERGED Mean Seed Emergence EC 0.6 EC 2 EC 2.5 EC 3 EC 4 Mean emergence percentage did not show a definite relationship with irrigation water salinity But time to germination increased with increasing irrigation water salinity 0 AZ 1904 Joe Parker S Select Paprika 25 Paprika 70 PEPPER VARIETIES Baath et al., 2015

17 Relative Height (cm) Saline Water Treatments Initially there were no differences in mean height of 6 chile pepper cultivars with increasing irrigation water salinity 0.4 On day 40, differences were observed Days since emergence ds/m ppm ds/m ds/m ds/m ppm ppm ppm Subsequently differences started to become more pronounced

18 Days to flowering decreased with increasing irrigation water salinity Treatments Experiment 1 Experiment 2 Mg/L Days to flowering Days to flowering 400 (control) a a a a b b b b LSD (0.05)

19 5.35 Biomass yield (T/ha) All chile peppers irrigated with the same type of water had similar biomass yields Irrigation Water salinity, mg/l Yields became significantly lower with increasing irrigation water salinity

20 Evapotranspiration (cm) Relative yield mg/l ds/m 3 ds/m 5 ds/m 8 ds/m AZ 1904 Joe E. Parker Sandia Select LB Days Since Emergence Soil salinity saturated paste extract, mg/l Yield decline observed for chile peppers irrigated with water > 2000 mg/l Early fruiting observed in brackish and RO water treatments

21 Leaching Fraction Leaching Fraction NuMex Joe E. Parker 0.6 ds/m 3 ds/m 5 ds/m 8 ds/m NuMex Sandia Select 0.6 ds/m ds/m ds/m Days after Thinning 8 ds/m Inverse relationship between LF and Growth (ET and yield) Days after Thinning

22 Photosynthetic rate Stomatal Conductance Transpiration rate Photosynthetic rate, Stomatal conductance and transpiration rate decreased with increasing irrigation water salinity

23 Chile peepers show yield decline when irrigated with brackish groundwater and RO concentrate What to do with RO concentrate? Irrigate Halophytes? Potential forage crops? Flores et al., 2016; Ozturk et al., 2017

24 Food Security also involves animals: Use of Brackish water for Fodder Common Name Scientific Name Barley Triticale Mesa Pepperwort Switchgrass Hordeum vulgare Triticum aestivum x Secale cereale Lepidium alyssoides Panicum virgatum Type Food Food Biomass Biomass Common Name Fourwing Saltbush Inland Saltgrass Scientific Name Atriplex canescens Distichlis stricta Type Fodder Fodder Flores et al., Journal of Seed Science and Technology

25 ET (cm) ET (cm) 80 Atriplex 80 Lepidium ds/m Days Switchgrass 40 8 ds/m Flores et al., Journal of Arid Environments Days

26 Sand grown Clay grown Species Treatment Mean (g) ± SE Mean (g) ± SE A. canescens ± 0.24 b 1.73 ± 0.22 a (Atriplex) ± 0.19 ab 1.51 ± 0.28 a ± 0.24 a 1.98 ± 0.17 a H. vulgare ± 0.27 a 2.48 ± 0.23 b (Barley) ± 0.09 a 3.36 ± 0.16 a ± 0.29 a 2.88 ± 0.20 ab L. alyssoides ± 0.07 a 0.54 ± 0.09 a (Mesa pepperwort) ± 0.08 a 0.72 ± 0.14 a ± 0.11 a 0.60 ± 0.10 a D. stricta ± 0.09 a 0.87 ± 0.12 a (Inland saltgrass) ± 0.12 a 0.78 ± 0.11 a ± 0.11 a 0.94 ± 0.04 a P. virgatum ± 0.10 a 0.09 ± 0.02 a (Switchgrass) ± 0.07 b 0.02 ± 0.01 b ± 0.10 c 0.02 ± 0.00 b Triticosecale ± 0.34 a 1.61 ± 0.14 b (Triticale) ± 0.14 a 2.14 ± 0.15 a ± 0.22 a 1.94 ± 0.09 ab

27 Season 1 Season 2 Species Treatment (mg/l) Fresh Wt (g) ± SE Fresh Wt (g) ± SE H. Vulgare L ± ± 1.46 a Barley ± ± 1.37 a ± ± 0.98 b ± ± 0.80 a xtriticosecale ± 0.53 c ± 0.87 Triticale ± 0.49 bc ± 1.28 Wheat x Rye ± 1.17 ba ± ± 0.99 a ± 1.04

28 Leaching Fractions Sand- Atriplex Sand- Barley EC 0.6 EC 4.1 EC 8.0 EC 0.6 EC 4.1 EC Sand- Lepidium EC 0.6 EC 4.1 EC 8.0 Sand- Switchgrass EC 0.6 EC 4.1 EC Sand- NiPa EC 0.6 EC 4.1 EC 8.0 Sand- Triticale EC 0.6 EC 4.1 EC 8.0

29 Photosynthetic Rate 0.4 Stomatal Conductance Transpiration Rate Irrigation water salinity influence on all species: No significant differences

30 Ion balance for Mg 2+, Na +, Ca 2+, and Cl - ions in the irrigation water, BGW (EC 5), RO1 (EC 8) and RO2 (EC 10) Total in Irrigation (mg) Total in Leachate (mg) Total in Biomass (mg) Total in Soil (mg) Water Na Ca Mg Cl Na Ca Mg Cl Na Ca Mg Cl Na Ca Mg Cl H. vulgare EC EC EC EC xtriticosecale EC EC EC EC

31 For Chile, irrigation with increasing water salinity resulted in: Less and delayed emergence Early flowering Low photosynthetic rate and stomatal conductance Considerable decrease in plant height and total biomass For Halophytes, irrigation with increasing water salinity: Delayed emergence Summary No significant differences in photosynthetic rate, stomatal conductance and transpiration Total biomass yields unchanged except for switchgrass For salinity management, brackish groundwater must be treated and the treated water can be used for irrigation. The RO concentrate can be used to irrigate halophytes but an efficient irrigation schedule needs to be made

32 ACKNOWLEDGEMENT Grad and Undergrad students and postdoc (Kellum, Flores, Sharma, Ozturk, Baath, Fernandez, and Gonzalez) John" Kaichiro and Tome Nakayama Professorship and Chair endowment Brackish Groundwater National Desalination Research Facility NMSU Agricultural Experiment Station WRRI NMSU

33 Improving Water Use Efficiency Using Fresh Surface and Groundwater Improved Irrigation methods Evaporation control Improved water delivery Sustainable yield and quality

34 Hay and Pecans, Dairy and Cattle ranching NM acreage: 8000 acres (40.7% of US Chile acreage) $ 500 million processed value Moderately salt sensitive (EC e 1.5 ds/m) NaCl as dominant salt NaCl vs Natural Groundwater NMDA statistics, 2014 Maas and Hoffman, 1977

35 Yield (Mg/ha) a. Control b. PRDv 20 cm Since irrigation water was of good quality, Leaching Fractions (volume basis) were near zero for PRDv and PRDc in 2014 ET (cm) c. PRDc Sharma et al., 2015; Hort Science 20 0 Control PRDv PRDc

36 Ci/Ca Photosynthetic rate (P n ) Stomatal conductance (g s ) Transpiration rates (T) Leaf temperature Ratio of intercellular to ambient CO 2 concentrations (Ci/Ca) A Control PRDv PRDc 5/24/2013 6/7/2013 7/20/2013 8/21/2013